Flunarizine Induced Parkinsonism in Migraine Group: A Nationwide Population-Based Study

The primary objective of this guideline is to assist the practitioner in choosing an appropriate prophylactic medication for an individual with migraine, based on current evidence in the medical literature and expert consensus. This guideline is focused on patients with episodic migraine (headache on ≤ 14 days a month). Through a comprehensive search strategy, randomized, double blind, controlled trials of drug treatments for migraine prophylaxis and relevant Cochrane reviews were identified. Studies were graded according to criteria developed by the US Preventive Services Task Force. Recommendations were graded according to the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group. In addition, a general literature review and expert consensus were used for aspects of prophylactic therapy for which randomized controlled trials are not available. Prophylactic drug choice should be based on evidence for efficacy, side-effect profile, migraine clinical features, and co-existing disorders. Based on our review, 11 prophylactic drugs received a strong recommendation for use (topiramate, propranolol, nadolol, metoprolol, amitriptyline, gabapentin, candesartan, butterbur, riboflavin, coenzyme Q10, and magnesium citrate) and 6 received a weak recommendation (divalproex sodium, flunarizine, pizotifen, venlafaxine, verapamil, and lisinopril). Quality of evidence for different medications varied from high to low. Prophylactic treatment strategies were developed to assist the practitioner in selecting a prophylactic drug for specific clinical situations. These strategies included: first time strategies for patients who have not had prophylaxis before (a beta-blocker and a tricyclic strategy), low side effect strategies (including both drug and herbal/vitamin/mineral strategies), a strategy for patients with high body mass index, strategies for patients with co-existent hypertension or with co-existent depression and /or anxiety, and additional monotherapy drug strategies for patients who have failed previous prophylactic trials. Further strategies included a refractory migraine strategy and strategies for prophylaxis during pregnancy and lactation. There is good evidence from randomized controlled trials for use of a number of different prophylactic medications in patients with migraine. Medication choice for an individual patient requires careful consideration of patient clinical features.

Twenty-six patients under treatment with the calcium channel blockers flunarizine (Fz) or cinnarizine (Cz) were examined-with single-photon emission computed tomography using [123I]iodobenzamide as a ligand. The striatal dopamine D2 receptor-binding potential was determined and found to be reduced by 14 to 63% (39.5 +/- 15.0%; p 6 months had significantly larger reductions than patients treated for a shorter period. Parkinsonian symptoms were only seen in patients older than 50 years. Our findings prove a neuroleptic-like action of Fz and Cz, which seems to be the major reason for their extrapyramidal side effects. Older age and long-term treatment are predisposing factors for these effects.